In 1986, the National Institute of Child Health and Human Development created the Maternal Fetal Medicine Units (MFMU) Network, consisting of a number of major academic clinical centers, a data coordinating center, and the Institute itself. The purpose of the Network was to conduct clinical research aimed at reducing the risk of adverse pregnancy and infant outcome with the ultimate purpose of contributing to the body of well conducted studies on which to base medical decisions in obstetrics and neonatology. At present the MFMU Network is planning, conducting and analyzing multiple randomized clinical trials and observational studies in various aspects of perinatal medicine such as preterm birth prevention, prevention of cerebral palsy, prevention of preeclampsia and the management of labor. The George Washington University Biostatistics Center presents this proposal to continue to serve as the data coordinating center for the Network. Our purpose is to provide expertise and support in study design, study conduct and statistical analysis. We will provide statistical leadership in the design of the study, prepare interim analyses, and perform final analyses in an expeditious and timely manner. We will prepare study documents, including protocols, manuals of operations and case report forms, and we will continue to provide a comprehensive data processing system including distributed and central data entry, data base management and data quality control. We will assist investigators in preparation of manuscripts and abstracts from study results and we will archive the data for public access. We will also provide administrative support such as: arrangement of logistical services for provision of study drugs and laboratory assays, maintenance of the MFMU Network website, coordination of meetings, training sessions and outcome reviews. We will manage resources effectively, so that we can start new studies in a timely manner. In summary, we will participate as full members of the Network with the common goal of understanding and improving the course of pregnancy and neonatal outcome.